Both OSHA and the International Fire Code use the Lethal-Dose 50 (LD50) to establish the toxicity of hazardous chemicals/materials and both use the metric milligram per kilogram of body weight in their assessments. Just so we all have an idea of how small a milligram is…
- One (1) grain of sand weighs 1 mg
- An average-sized ant will weigh around 2 mg
So we are talking about some REALLY toxic materials when they have an LD50 less than 50 mg/kg.